Results obtained in our laboratory have shown that certain strains of Clostridium perfringens produce an enterotoxin responsible for food poisoning caused by this organism. Our proposed research will allow us to continue our investigations on methods for purification of enterotoxin as well as characterization of purified enterotoxin. Further investigation will be made of the mode of the action of enterotoxin in rat, rabbit, and primate animal models. The sensitivity of various tissue cultures to toxin will be ascertained with consideration of their potential usefulness in a bioassay as well as in determination of a specific binding site for the toxin. A paracrystalline inclusion produced during toxin formation and spore formation will be isolated and compared to enterotoxin by biochemical, serological and biological activity techniques. BIBLIOGRAPHIC REFERENCES: McDonel, J.L., and C.L. Duncan. 1975. Effects of Clostridium perfringens enterotoxin on metabolic indexes of everted rat ileal sacs. Infect. Immun. 12:274-280. McDonel, J.L., and C.L. Duncan. 1975. Histopathological effect of Clostridium perfringens enterotoxin in the rabbit ileum. Infect. Immun. 12:1214-1218.